US5889069A - High temperature syndiotactic styrene polymer foam - Google Patents

High temperature syndiotactic styrene polymer foam Download PDF

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US5889069A
US5889069A US08/893,149 US89314997A US5889069A US 5889069 A US5889069 A US 5889069A US 89314997 A US89314997 A US 89314997A US 5889069 A US5889069 A US 5889069A
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polymeric material
polyphenylene oxide
polymer
weight
polycarbonate
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US08/893,149
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Kyung W. Suh
Creston D. Shmidt
Daniel D. Imeokparia
Alan E. Platt
Thomas E. Wessel
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Dow Chemical Co
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Dow Chemical Co
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Assigned to DOW CHEMICAL COMPANY, THE reassignment DOW CHEMICAL COMPANY, THE ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: IMEOKPARIA, DANIEL D., PLATT, ALAN E., SHMIDT, CRESTON D., SUH, KYUNG W., WESSEL, THOMAS E.
Priority to PCT/US1998/014425 priority patent/WO1999003919A1/en
Priority to JP2000503140A priority patent/JP2001510218A/en
Priority to US09/227,020 priority patent/US6051621A/en
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
    • C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
    • C08L25/02—Homopolymers or copolymers of hydrocarbons
    • C08L25/04—Homopolymers or copolymers of styrene
    • C08L25/06—Polystyrene
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2325/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Derivatives of such polymers
    • C08J2325/02—Homopolymers or copolymers of hydrocarbons
    • C08J2325/04—Homopolymers or copolymers of styrene
    • C08J2325/06—Polystyrene
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2469/00—Characterised by the use of polycarbonates; Derivatives of polycarbonates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2471/00—Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2483/00—Characterised by the use of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen, or carbon only; Derivatives of such polymers
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L69/00—Compositions of polycarbonates; Compositions of derivatives of polycarbonates
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L71/00—Compositions of polyethers obtained by reactions forming an ether link in the main chain; Compositions of derivatives of such polymers
    • C08L71/08—Polyethers derived from hydroxy compounds or from their metallic derivatives
    • C08L71/10—Polyethers derived from hydroxy compounds or from their metallic derivatives from phenols
    • C08L71/12—Polyphenylene oxides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L83/00—Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
    • C08L83/04—Polysiloxanes

Definitions

  • This invention relates to crystalline thermoplastic blends exhibiting improved physical properties, and more particularly to low density, syndiotactic styrene polymer foam blends exhibiting excellent mechanical properties and high heat distortion temperatures.
  • Expanded materials or foams containing amorphous or atactic polystyrene have been widely used in a variety of applications because of their low density, low thermal conductivity, low cost and good energy absorption properties. Particular applications include thermal insulators, disposable containers, and protective packaging.
  • polystyrene Most of the important properties of polystyrene, including energy absorption, thermal resistivity, strength to weight ratio, and cost per unit volume, are strongly dependent on density and, therefore, can be easily adjusted by controlling the amount of expansion.
  • expanded polymeric materials other than polystyrene foam are often selected where certain nonstrength properties are important, particularly high temperature resistance.
  • syndiotactic polystyrene exhibits certain improved heat resistant properties as compared with atactic polystyrene. Specifically, syndiotactic polystyrene has a higher melting point than atactic polystyrene. However, the heat distortion temperature, an important thermal property for expanded polymeric materials, is only about 80° C. for compositions comprised of substantially pure syndiotactic polystyrene.
  • various rubber-like polymers and/or thermoplastic resins can be blended with syndiotactic polystyrene to control viscosity and the rate of crystallization.
  • atactic polystyrene, isotactic polystyrene, polyphenylene ethers, or mixtures thereof are compatible with syndiotactic polystyrene, and that by selecting the amount, type and molecular weight of these polymers, the expansion molding methods used for conventional crystalline resins, such as polyethylene and polypropylene, and for conventional non-crystalline resins, such as atactic polystyrene and polyvinyl chloride, can be applied.
  • the patent literature also discloses that syndiotactic polystyrene can be blended with polyphenylene ethers to provide compositions endowed with enhanced mechanical properties as compared to those containing amorphous polystyrene or isotactic polystyrene.
  • the literature does not suggest that polyphenylene ethers or any other materials can be added to syndiotactic polystyrene to improve the mechanical properties thereof at higher temperatures.
  • This invention provides styrene polymer materials exhibiting improved heat resistant properties and improved mechanical properties as compared with known expanded syndiotactic styrene polymer materials. Specifically, the syndiotactic styrene polymer materials of this invention exhibit improved heat distortion temperature, while simultaneously exhibiting improved compression strength, as compared with known syndiotactic styrene polymer materials.
  • the polymeric materials of this invention are obtained from a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart a heat distortion temperature which is at least about 130° C.
  • a polymer blend includes maleic anhydride modified polyphenylene oxide in amount which is sufficient to impart enhanced heat resistant properties.
  • a polymer blend includes from about 60% to about 80% syndiotactic styrene polymer by weight, and from about 40% to about 20% of an amorphous polymeric material by weight, wherein the amorphous polymeric material includes at least one of maleic anhydride modified polyphenylene oxide and a silicone elastomer.
  • a polymer blend includes syndiotactic polystyrene, polyphenylene oxide, and at least about 10% polycarbonate by weight.
  • stereotactic refers to polymers having a stereo regular structure of greater than 50% syndiotactic of a racemic triad as determined by C 13 nuclear magnetic resonance spectroscopy.
  • styrene polymers refers to polystyrene, poly(alkyl styrene), poly(halogenated styrene), poly(alkoxy styrene), polyvinyl benzylate or mixtures thereof, and copolymers containing syndiotactic styrene polymer blocks as main components.
  • Preferred styrene polymers include polystyrene, poly(p-methyl styrene), poly(m-methyl styrene), poly(p-tert-butyl styrene), poly(p-chlorostyrene), poly(m-chlorostyrene), poly(p-fluorostyrene), and a copolymer of styrene and p-methylstyrene.
  • the molecular weight of the styrene polymer used in this invention is not critical and can range from about 10,000 to about 10,000,000 or more. Styrene polymers having lower or higher molecular weights can however be used, although those having weight average molecular weights of at least 25,000 are preferred.
  • the molecular weight distribution of the styrene polymers is not critical and may be narrow or wide.
  • the syndiotactic polystyrene polymeric blends have been found particularly useful in the preparation of expanded or foamed plastics.
  • the amorphous polymeric materials which can be blended with syndiotactic styrene polymers in accordance with the principles of this invention include those amorphous polymers which when blended with a syndiotactic styrene polymer and expanded, form a foamed material having a heat distortion temperature which is substantially higher than the heat distortion temperature of foamed materials formed from an essentially pure syndiotactic styrene polymer.
  • the amorphous polymeric material should be capable of imparting a heat distortion temperature which is at least about 130° C., and more preferably at least about 200° C.
  • amorphous polymeric materials which have been successfully blended with syndiotactic styrene polymers and expanded to produce foamed materials exhibiting improved heat distortion temperatures include maleic anhydride modified polyphenylene oxide, polycarbonate, silicone elastomers, and/or combinations thereof.
  • Maleic anhydride modified polyphenylene oxide may be prepared by reactive extrusion of polyphenylene oxide with maleic anhydride and a suitable free radical initiator.
  • maleic anhydride is grafted to poly(2,6-dimethyl phenylene oxide in a twin screw extruder at 320° C.
  • the resulting maleic anhydride modified polyphenylene oxide is represented by the following general formula: ##STR1##
  • polyphenylene oxide refers to any of various homopolymers or heteropolymers having phenylene oxide repeat units and/or substituted phenylene oxide repeat units.
  • the ratio of maleic anhydride to polyphenylene oxide polymer can be higher or lower, and is not limited to three parts per 100 parts of polyphenylene oxide.
  • Maleic anhydride modified polyphenylene oxide can also be prepared by substituting either maleic acid or fumaric acid in place of maleic anhydride. Fumaric acid is presently preferred because it is non-toxic and easy to handle. The process results in about a 2% anhydride grafted to the polyphenylene oxide when three parts of maleic anhydride are used per 100 parts by weight of polyphenylene oxide.
  • silicone elastomers which have been advantageously employed in the polymer blends of this invention include TREFIL(® E501 or E601 which are commercially available from Toray Co.
  • binary blends of a syndiotactic styrene polymer and maleic anhydride modified polyphenylene oxide can be used to obtain expanded polymeric materials having a heat distortion temperature of at least 130° C., with heat distortion temperatures in excess of 200° C. being obtainable.
  • the binary blends of syndiotactic styrene polymer and maleic anhydride modified polyphenylene oxide also exhibit improved compressive strength and reduced intrinsic brittleness as compared to expanded polymeric materials consisting essentially of pure syndiotactic polystyrene.
  • Ternary blends consisting of syndiotactic styrene polymer, polycarbonate and maleic anhydride modified polyphenylene oxide, and ternary blends of syndiotactic styrene polymer, polycarbonate and silicone elastomer (TREFIL® E601) have been used to obtain foamed materials exhibiting exceptionally high heat distortion temperatures, while also exhibiting reduced intrinsic brittleness as compare with expanded materials obtained from polymeric compositions consisting essentially of pure syndiotactic polystyrene. Although less preferred because of lower compressive strength, the combination of 75% SPS and 25% polycarbonate also exhibits a heat distortion temperature greater than 200° C.
  • Another ternary blend exhibiting improved heat distortion temperature properties consists of syndiotactic polystyrene, at least 10% polycarbonate by weight, and at least 10% polyphenylene oxide by weight.
  • the expanded polymeric materials of this invention are preferably obtained from a polymer blend comprising at least 50% syndiotactic styrene polymer by weight. More preferably, the polymer blend includes from about 50% to about 80%, and most preferably from about 60% to about 80% syndiotactic styrene polymer by weight.
  • Compositions containing maleic anhydride modified polyphenylene oxide preferably contain at least about 10% maleic anhydride modified polyphenylene oxide by weight.
  • the styrene polymer-containing crystalline thermoplastic blends of this invention can be expanded to form foamed materials and articles using known molding and extrusion techniques including standard molding techniques and extrusion techniques.
  • the styrene polymer-containing polymer blends of this invention can be combined with a foaming agent to produce expandable polymeric beads containing an integral blowing agent.
  • the expandable beads can be subsequently heated in a mold to form a desired article.
  • the syndiotactic styrene polymer containing polymeric blends of this invention can be extruded to form sheets, films, slabs, tubes or other extruded shapes.
  • the foaming agent can generally be mixed with the syndiotactic styrene polymer containing polymeric blend either before molding or extruding, or at the time of molding or extruding. There are no special limitations on the foaming agent which is to be used in practicing the present invention.
  • the present syndiotactic polystyrene-containing polymer foam blends are generally prepared by heating a syndiotactic polystyrene-containing polymer blend to form a plasticized or melt polymer material, incorporating therein a blowing agent to form a foamable gel, and extruding the gel through a die to form the foam product.
  • a syndiotactic polystyrene-containing polymer blend Prior to mixing with the blowing agent, the polymer material is heated to a temperature at or above its glass transition temperature or melting point.
  • the blowing agent may be incorporated or mixed into the melt polymer material by any means known in the art such a with an extruder, mixer, blender, or the like.
  • the blowing agent is mixed with the melt polymer material at an elevated pressure sufficient to prevent substantial expansion of the melt polymer material and to generally disperse the blowing agent homogeneously therein.
  • a nucleator may be blended in the polymer melt or dry blended with the polymer material prior to plasticizing or melting.
  • the foamable gel is typically cooled to a lower temperature to optimize physical characteristics of the foam structure.
  • the gel may be cooled in the extruder or other mixing device or in separate coolers.
  • the gel is then extruded or conveyed through a die of desired shape to a zone of reduced or lower pressure to form the foam structure.
  • the zone of lower pressure is at a pressure lower than that in which the foamable gel is maintained prior to extrusion through the die.
  • the lower pressure may be superatmospheric or subatmospheric (vacuum), but is preferably at an atmospheric level.
  • the use of a dynamic cooling device which allows the gel to be continuously homogenized while being cooled down to the foaming temperature is preferred to avoid initiation of crystallization and freezing at the metal interfaces of the extrusion apparatus.
  • the crystalline engineering thermoplastic resins of this invention are preferably extruded with blowing agent injected into the molten polymer, with the mixture cooled to the foaming temperature using dynamic cooling devices and expanded through an extrusion dye in the lower pressure region.
  • syndiotactic polystyrene was dry blended with a nucleator and amorphous polymeric additives as described above.
  • the blend was introduced into a Werner Pfleiderer 30 millimeter non-intermeshing, co-rotating twin screw extruder with extruder zone 1 at 245° C., zone 2 at 260° C., zone 3 at 246° C., zone 4 at 243° C., and zone 5 at 260° C., and the dye gel temperature at 233° C.
  • the dye was attached to the end of a dynamic cooling device to cool the gel to the foaming temperature to facilitate high production rates.
  • Blowing agents useful in making the present foam structure include inorganic agents, organic blowing agents and chemical blowing agents.
  • Suitable inorganic blowing agents include carbon dioxide, nitrogen, argon, water, air nitrogen, and helium.
  • Organic blowing agents include aliphatic hydrocarbons having 1-9 carbon atoms, aliphatic alcohols having 1-3 carbon atoms, and fully and partially halogenated aliphatic hydrocarbons having 1-4 carbon atoms.
  • Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane, and the like.
  • Aliphatic alcohols include methanol, ethanol, n-propanol, and isopropanol.
  • Fully and partially halogenated aliphatic hydrocarbons include fluorocarbons, chlorocarbons, and chlorofluorocarbons.
  • fluorocarbons include methyl fluoride, perfluoromethane, ethyl fluoride, 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a), 1,1,1,2-tetrafluoroethane (HFC-134a), pentafluoroethane, difluoromethane, perfluoroethane, 2,2-difluoropropane, 1,1,1-trifluoropropane, perfluoropropane, dichloropropane, difluoropropane, perfluorobutane, perfluorocyclobutane.
  • Partially halogenated chlorocarbons and chlorofluorocarbons for use in this invention include methyl chloride, methylene chloride, ethyl chloride, 1,1,1-trichloroethane, 1,1-dichloro-1-fluoroethane (HFC-141b), 1-chloro-1,1-difluoroethane (HCFC-142), chlorodifluoromethane (HCFC-22), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1-chloro-1,2,2,2-tetrafluoroethane (HCFC-124).
  • Fully halogenated chloroflurorcarbons include trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), trichlorotrifluoroethane (CFC-113), 1,1,1-trifluoroethane, pentafluoroethane, dichlorotetrafluoroethane (CFC-114), chloroheptafluoropropane, and dichlorohexafluoropropane.
  • CFC-11 trichloromonofluoromethane
  • CFC-12 dichlorodifluoromethane
  • CFC-113 trichlorotrifluoroethane
  • 1,1,1-trifluoroethane pentafluoroethane
  • dichlorotetrafluoroethane CFC-114
  • chloroheptafluoropropane dichlorohexafluoropropane
  • Chemical blowing agents include azodicarbonaminde, azodiisobutyronitrile, benzenesulfonhydrazide, 4,4-oxybenzene sulfonyl-semicarbazide, p-toluene sulfonyl semicarbazide, barium azodicarboxylate, N,N'-dimethyl-N,N'-dinitrosoterephthalamide, and trihydrazino triazine.
  • the amount of blowing agent incorporated into the polymer melt material to make a foam-forming polymer gel is from about 0.2 to about 5.0 gram-moles per kilogram of polymer, preferably from about 0.5 to about 3.0 gram-moles per kilogram of polymer, and most preferably from about 1.0 to 2.50 gram-moles per kilogram of polymer.
  • syndiotactic styrene polymer containing blends of this invention may contain, in addition to the amorphous polymeric material which is used to impart improved heat distortion temperatures and improved mechanical properties, various additives such as lubricants, antioxidants, inorganic fillers, ultraviolet ray absorbers, heat stabilizers, flame retardants, anti-static agents, nucleating agents and colorants.
  • Syndiotactic polystyrene was dry blended with a nucleator and introduced into a 30 millimeter non-intermeshing, co-rotating twin screw extruder (Werner Pfleiderer) with an extruder zone 1 temperature of 245° C., a zone 2 temperature of 260° C., a zone 3 temperature of 246° C., a zone 4 temperature of 243° C., a zone 5 temperature of 260° C., and a die gel temperature of 233° C.
  • the die was attached to the end of the twin screw extruder discharge.
  • the blowing agent HCFC-123 was introduced into zone 2 of the extruder.
  • the nucleator talc was added at about 0.5 to about 1.0 pph levels to control cell size.
  • the foamed materials in accordance with the invention generally exhibited higher heat deflection temperatures than foamed materials obtained from substantially pure syndiotactic polystyrene, and various binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate. Additionally, by reference to the values of the comparative flex product per square inch test, it is seen that the more preferred foamed materials of this invention exhibit reduced intrinsic brittleness as compared with foamed materials obtained from substantially pure syndiotactic polystyrene, and various binary blends of syndiotactic polystyrene with either polyphenylene oxide or polycarbonate. 75% SPS and 25% PC is less preferred, since while it exhibits higher HDT, its compressive strength is less than that of 100% SPS.
  • the foamed materials of this invention generally exhibit improved compressive strength relative to foamed materials obtained from substantially pure syndiotactic polystyrene, and foamed materials obtained from binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate.
  • Table 2 illustrates that foamed materials in accordance with this invention can be successfully prepared using techniques which are generally successfully employed in preparing foamed materials from substantially pure syndiotactic polystyrene or binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate.

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Abstract

Foamed polymeric materials exhibiting improved heat resistant properties and improved mechanical properties, as compared with known foamed styrene polymer materials, are obtained by expanding a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart enhanced heat resistant properties to the blend.

Description

FIELD OF THE INVENTION
This invention relates to crystalline thermoplastic blends exhibiting improved physical properties, and more particularly to low density, syndiotactic styrene polymer foam blends exhibiting excellent mechanical properties and high heat distortion temperatures.
BACKGROUND OF THE INVENTION
Expanded materials or foams containing amorphous or atactic polystyrene have been widely used in a variety of applications because of their low density, low thermal conductivity, low cost and good energy absorption properties. Particular applications include thermal insulators, disposable containers, and protective packaging.
Most of the important properties of polystyrene, including energy absorption, thermal resistivity, strength to weight ratio, and cost per unit volume, are strongly dependent on density and, therefore, can be easily adjusted by controlling the amount of expansion. However, expanded polymeric materials other than polystyrene foam are often selected where certain nonstrength properties are important, particularly high temperature resistance.
It is known that syndiotactic polystyrene exhibits certain improved heat resistant properties as compared with atactic polystyrene. Specifically, syndiotactic polystyrene has a higher melting point than atactic polystyrene. However, the heat distortion temperature, an important thermal property for expanded polymeric materials, is only about 80° C. for compositions comprised of substantially pure syndiotactic polystyrene. The patent literature suggests that various rubber-like polymers and/or thermoplastic resins can be blended with syndiotactic polystyrene to control viscosity and the rate of crystallization. In particular, it has been disclosed that atactic polystyrene, isotactic polystyrene, polyphenylene ethers, or mixtures thereof are compatible with syndiotactic polystyrene, and that by selecting the amount, type and molecular weight of these polymers, the expansion molding methods used for conventional crystalline resins, such as polyethylene and polypropylene, and for conventional non-crystalline resins, such as atactic polystyrene and polyvinyl chloride, can be applied. The patent literature also discloses that syndiotactic polystyrene can be blended with polyphenylene ethers to provide compositions endowed with enhanced mechanical properties as compared to those containing amorphous polystyrene or isotactic polystyrene. However, the literature does not suggest that polyphenylene ethers or any other materials can be added to syndiotactic polystyrene to improve the mechanical properties thereof at higher temperatures.
SUMMARY OF THE INVENTION
This invention provides styrene polymer materials exhibiting improved heat resistant properties and improved mechanical properties as compared with known expanded syndiotactic styrene polymer materials. Specifically, the syndiotactic styrene polymer materials of this invention exhibit improved heat distortion temperature, while simultaneously exhibiting improved compression strength, as compared with known syndiotactic styrene polymer materials.
The polymeric materials of this invention are obtained from a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart a heat distortion temperature which is at least about 130° C.
In accordance with one aspect of the invention, a polymer blend includes maleic anhydride modified polyphenylene oxide in amount which is sufficient to impart enhanced heat resistant properties.
In accordance with another aspect of the invention, a polymer blend includes from about 60% to about 80% syndiotactic styrene polymer by weight, and from about 40% to about 20% of an amorphous polymeric material by weight, wherein the amorphous polymeric material includes at least one of maleic anhydride modified polyphenylene oxide and a silicone elastomer.
In accordance with a further aspect of the invention, a polymer blend includes syndiotactic polystyrene, polyphenylene oxide, and at least about 10% polycarbonate by weight.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As used herein, the word "syndiotactic" refers to polymers having a stereo regular structure of greater than 50% syndiotactic of a racemic triad as determined by C13 nuclear magnetic resonance spectroscopy.
As used herein, the expression "styrene polymers" refers to polystyrene, poly(alkyl styrene), poly(halogenated styrene), poly(alkoxy styrene), polyvinyl benzylate or mixtures thereof, and copolymers containing syndiotactic styrene polymer blocks as main components. Preferred styrene polymers include polystyrene, poly(p-methyl styrene), poly(m-methyl styrene), poly(p-tert-butyl styrene), poly(p-chlorostyrene), poly(m-chlorostyrene), poly(p-fluorostyrene), and a copolymer of styrene and p-methylstyrene.
The molecular weight of the styrene polymer used in this invention is not critical and can range from about 10,000 to about 10,000,000 or more. Styrene polymers having lower or higher molecular weights can however be used, although those having weight average molecular weights of at least 25,000 are preferred. The molecular weight distribution of the styrene polymers is not critical and may be narrow or wide.
Methods of producing syndiotactic styrene polymers are well known and need not be discussed herein. See for example U.S. Pat. No. 5,066,741 which mentions several well known techniques.
The syndiotactic polystyrene polymeric blends have been found particularly useful in the preparation of expanded or foamed plastics. The amorphous polymeric materials which can be blended with syndiotactic styrene polymers in accordance with the principles of this invention include those amorphous polymers which when blended with a syndiotactic styrene polymer and expanded, form a foamed material having a heat distortion temperature which is substantially higher than the heat distortion temperature of foamed materials formed from an essentially pure syndiotactic styrene polymer. More specifically, the amorphous polymeric material should be capable of imparting a heat distortion temperature which is at least about 130° C., and more preferably at least about 200° C. Examples of amorphous polymeric materials which have been successfully blended with syndiotactic styrene polymers and expanded to produce foamed materials exhibiting improved heat distortion temperatures include maleic anhydride modified polyphenylene oxide, polycarbonate, silicone elastomers, and/or combinations thereof. Maleic anhydride modified polyphenylene oxide may be prepared by reactive extrusion of polyphenylene oxide with maleic anhydride and a suitable free radical initiator. As a specific example, maleic anhydride is grafted to poly(2,6-dimethyl phenylene oxide in a twin screw extruder at 320° C. Three parts of maleic anhydride and two parts of a free radical initiator, such as 2,3-diphenyl-2,3-dimethyl butane, are fed into the extruder per 100 parts by weight of polyphenylene oxide. The resulting maleic anhydride modified polyphenylene oxide is represented by the following general formula: ##STR1## The term "polyphenylene oxide" as used herein refers to any of various homopolymers or heteropolymers having phenylene oxide repeat units and/or substituted phenylene oxide repeat units. The ratio of maleic anhydride to polyphenylene oxide polymer can be higher or lower, and is not limited to three parts per 100 parts of polyphenylene oxide. Maleic anhydride modified polyphenylene oxide can also be prepared by substituting either maleic acid or fumaric acid in place of maleic anhydride. Fumaric acid is presently preferred because it is non-toxic and easy to handle. The process results in about a 2% anhydride grafted to the polyphenylene oxide when three parts of maleic anhydride are used per 100 parts by weight of polyphenylene oxide. Examples of silicone elastomers which have been advantageously employed in the polymer blends of this invention include TREFIL(® E501 or E601 which are commercially available from Toray Co. More specifically, it has been found that binary blends of a syndiotactic styrene polymer and maleic anhydride modified polyphenylene oxide can be used to obtain expanded polymeric materials having a heat distortion temperature of at least 130° C., with heat distortion temperatures in excess of 200° C. being obtainable. The binary blends of syndiotactic styrene polymer and maleic anhydride modified polyphenylene oxide also exhibit improved compressive strength and reduced intrinsic brittleness as compared to expanded polymeric materials consisting essentially of pure syndiotactic polystyrene.
Ternary blends consisting of syndiotactic styrene polymer, polycarbonate and maleic anhydride modified polyphenylene oxide, and ternary blends of syndiotactic styrene polymer, polycarbonate and silicone elastomer (TREFIL® E601) have been used to obtain foamed materials exhibiting exceptionally high heat distortion temperatures, while also exhibiting reduced intrinsic brittleness as compare with expanded materials obtained from polymeric compositions consisting essentially of pure syndiotactic polystyrene. Although less preferred because of lower compressive strength, the combination of 75% SPS and 25% polycarbonate also exhibits a heat distortion temperature greater than 200° C.
Another ternary blend exhibiting improved heat distortion temperature properties consists of syndiotactic polystyrene, at least 10% polycarbonate by weight, and at least 10% polyphenylene oxide by weight.
Improved properties can be achieved using various proportions of syndiotactic styrene polymer and the amorphous polymeric materials. However, the expanded polymeric materials of this invention are preferably obtained from a polymer blend comprising at least 50% syndiotactic styrene polymer by weight. More preferably, the polymer blend includes from about 50% to about 80%, and most preferably from about 60% to about 80% syndiotactic styrene polymer by weight. Compositions containing maleic anhydride modified polyphenylene oxide preferably contain at least about 10% maleic anhydride modified polyphenylene oxide by weight.
The styrene polymer-containing crystalline thermoplastic blends of this invention can be expanded to form foamed materials and articles using known molding and extrusion techniques including standard molding techniques and extrusion techniques. For example, the styrene polymer-containing polymer blends of this invention can be combined with a foaming agent to produce expandable polymeric beads containing an integral blowing agent. The expandable beads can be subsequently heated in a mold to form a desired article. As another example, the syndiotactic styrene polymer containing polymeric blends of this invention can be extruded to form sheets, films, slabs, tubes or other extruded shapes.
The foaming agent can generally be mixed with the syndiotactic styrene polymer containing polymeric blend either before molding or extruding, or at the time of molding or extruding. There are no special limitations on the foaming agent which is to be used in practicing the present invention.
The present syndiotactic polystyrene-containing polymer foam blends are generally prepared by heating a syndiotactic polystyrene-containing polymer blend to form a plasticized or melt polymer material, incorporating therein a blowing agent to form a foamable gel, and extruding the gel through a die to form the foam product. Prior to mixing with the blowing agent, the polymer material is heated to a temperature at or above its glass transition temperature or melting point. The blowing agent may be incorporated or mixed into the melt polymer material by any means known in the art such a with an extruder, mixer, blender, or the like. The blowing agent is mixed with the melt polymer material at an elevated pressure sufficient to prevent substantial expansion of the melt polymer material and to generally disperse the blowing agent homogeneously therein. Optionally, a nucleator may be blended in the polymer melt or dry blended with the polymer material prior to plasticizing or melting. The foamable gel is typically cooled to a lower temperature to optimize physical characteristics of the foam structure. The gel may be cooled in the extruder or other mixing device or in separate coolers. The gel is then extruded or conveyed through a die of desired shape to a zone of reduced or lower pressure to form the foam structure. The zone of lower pressure is at a pressure lower than that in which the foamable gel is maintained prior to extrusion through the die. The lower pressure may be superatmospheric or subatmospheric (vacuum), but is preferably at an atmospheric level.
Because it is generally difficult to provide a non-freezing plug flow through static cooling devices with crystalline engineering thermoplastic resins, the use of a dynamic cooling device which allows the gel to be continuously homogenized while being cooled down to the foaming temperature is preferred to avoid initiation of crystallization and freezing at the metal interfaces of the extrusion apparatus. Accordingly, the crystalline engineering thermoplastic resins of this invention are preferably extruded with blowing agent injected into the molten polymer, with the mixture cooled to the foaming temperature using dynamic cooling devices and expanded through an extrusion dye in the lower pressure region. For example, syndiotactic polystyrene was dry blended with a nucleator and amorphous polymeric additives as described above. The blend was introduced into a Werner Pfleiderer 30 millimeter non-intermeshing, co-rotating twin screw extruder with extruder zone 1 at 245° C., zone 2 at 260° C., zone 3 at 246° C., zone 4 at 243° C., and zone 5 at 260° C., and the dye gel temperature at 233° C. The dye was attached to the end of a dynamic cooling device to cool the gel to the foaming temperature to facilitate high production rates.
Blowing agents useful in making the present foam structure include inorganic agents, organic blowing agents and chemical blowing agents. Suitable inorganic blowing agents include carbon dioxide, nitrogen, argon, water, air nitrogen, and helium. Organic blowing agents include aliphatic hydrocarbons having 1-9 carbon atoms, aliphatic alcohols having 1-3 carbon atoms, and fully and partially halogenated aliphatic hydrocarbons having 1-4 carbon atoms. Aliphatic hydrocarbons include methane, ethane, propane, n-butane, isobutane, n-pentane, isopentane, neopentane, and the like. Aliphatic alcohols include methanol, ethanol, n-propanol, and isopropanol. Fully and partially halogenated aliphatic hydrocarbons include fluorocarbons, chlorocarbons, and chlorofluorocarbons. Examples of fluorocarbons include methyl fluoride, perfluoromethane, ethyl fluoride, 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a), 1,1,1,2-tetrafluoroethane (HFC-134a), pentafluoroethane, difluoromethane, perfluoroethane, 2,2-difluoropropane, 1,1,1-trifluoropropane, perfluoropropane, dichloropropane, difluoropropane, perfluorobutane, perfluorocyclobutane. Partially halogenated chlorocarbons and chlorofluorocarbons for use in this invention include methyl chloride, methylene chloride, ethyl chloride, 1,1,1-trichloroethane, 1,1-dichloro-1-fluoroethane (HFC-141b), 1-chloro-1,1-difluoroethane (HCFC-142), chlorodifluoromethane (HCFC-22), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1-chloro-1,2,2,2-tetrafluoroethane (HCFC-124). Fully halogenated chloroflurorcarbons include trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), trichlorotrifluoroethane (CFC-113), 1,1,1-trifluoroethane, pentafluoroethane, dichlorotetrafluoroethane (CFC-114), chloroheptafluoropropane, and dichlorohexafluoropropane. Chemical blowing agents include azodicarbonaminde, azodiisobutyronitrile, benzenesulfonhydrazide, 4,4-oxybenzene sulfonyl-semicarbazide, p-toluene sulfonyl semicarbazide, barium azodicarboxylate, N,N'-dimethyl-N,N'-dinitrosoterephthalamide, and trihydrazino triazine. The amount of blowing agent incorporated into the polymer melt material to make a foam-forming polymer gel is from about 0.2 to about 5.0 gram-moles per kilogram of polymer, preferably from about 0.5 to about 3.0 gram-moles per kilogram of polymer, and most preferably from about 1.0 to 2.50 gram-moles per kilogram of polymer.
The syndiotactic styrene polymer containing blends of this invention may contain, in addition to the amorphous polymeric material which is used to impart improved heat distortion temperatures and improved mechanical properties, various additives such as lubricants, antioxidants, inorganic fillers, ultraviolet ray absorbers, heat stabilizers, flame retardants, anti-static agents, nucleating agents and colorants.
EXAMPLES
Syndiotactic polystyrene (SPS) was dry blended with a nucleator and introduced into a 30 millimeter non-intermeshing, co-rotating twin screw extruder (Werner Pfleiderer) with an extruder zone 1 temperature of 245° C., a zone 2 temperature of 260° C., a zone 3 temperature of 246° C., a zone 4 temperature of 243° C., a zone 5 temperature of 260° C., and a die gel temperature of 233° C. The die was attached to the end of the twin screw extruder discharge. The blowing agent (HCFC-123) was introduced into zone 2 of the extruder. The nucleator (talc) was added at about 0.5 to about 1.0 pph levels to control cell size.
Various samples were prepared in a similar manner by dry blending syndiotactic polystyrene with one or more additives including various combinations of polyphenylene oxide (PPO), maleic anhydride modified polyphenylene oxide (MAPPO), polycarbonate (PC), and a silicone elastomer (E601).
The various samples were analyzed and subjecting to testing to determine density, cell size, heat distortion temperature (HDT), comparative flex product per square inch, compressive strength in the vertical direction and in the extruded direction. Heat distortion temperatures was determined in accordance with ASTM D2126-76, Part 36, density in accordance with ASTM D3575-91, compressive strength in accordance with ASTM D1621 and comparative flex in accordance with ASTM D790-81, with area normalization to account for differences in sample sizes. The results of these tests are summarized in Tables 1A and 1B. The percentages set forth in the tables represent weight percents.
                                  TABLE 1A
__________________________________________________________________________
SAMPLE             DENSITY.sup.1
                         CELL SIZE
                               HDT.sup.2
                                    COMPARATIVE FLEX
NO   COMPOSITION   (pcf) (mm)  (C)  PRODUCT PER SQR. IN.sup.3
__________________________________________________________________________
1    100% SPS.sup.5
                   4.25  1.62   80  0.403
2    80% SPS/20% MAPPO
                   3.55  0.67  130˜140
                                    0.516
3    60% SPS/40% MAPPO
                   3.60  0.75  >200 0.617
4    75% SPS/15% PC/10% MAPPO
                   4.34  0.62  >200 0.627
5    80% SPS/15% PC/5% E601
                   5.15  0.18  >200 0.434
6    94% SPS/6% PPO
                   3.41  0.86  >110 0.261
7    85% SPS/15% PPO.sup.5
                   3.89  --    >120 0.54
8    74% SPS/26% PPO.sup.5
                   4.34  1.01  100˜120
                                    2.473
9    95% SPS/5% PC.sup.5
                   3.5   1.01  --   0.199
10   94% SPS/6% PC.sup.5
                   5.04  1.50  >110 0.181
11   85% SPS/15% PC.sup.5
                   3.62  1.08  --   0.170
12   75% SPS/25% PC
                   3.66  1.20  >200 0.254
__________________________________________________________________________

                                  TABLE 1B
__________________________________________________________________________
SAMPLE             DENSITY.sup.1
                         CELL SIZE
                               HDT.sup.2
                                    COMPRESSIVE STRENGTH.sup.4
NO   COMPOSITION   (pcf) (mm)  (C)  VERTICAL
                                           EXTRUDED
__________________________________________________________________________
1    100% SPS.sup.5
                   4.25  1.62   80  20.4   28.2
2    80% SPS/20% MAPPO
                   3.55  0.67  130˜140
                                    29.9   43.8
3    60% SPS/40% MAPPO
                   3.60  0.75  >200 35.2   55.4
4    75% SPS/15% PC/10% MAPPO
                   4.34  0.62  >200 --     --
5    80% SPS/15% PC/5% E601
                   5.15  0.18  >200 --     --
7    85% SPS/15% PPO.sup.5
                   3.89  --    >120 18.4   53.9
12   75% SPS/25% PC
                   3.66  1.20  >200 17.0   21.4
13   75% SPS/20% PPO/5% PC.sup.5
                   3.41  0.86  <110 23.6   51.1
__________________________________________________________________________
 .sup.1 ASTM D357591
 .sup.2 ASTM D212676, Part 36
 .sup.3 Modified ASTM D79081 test, with area normalization to account for
 differences in sample sizes.
 .sup.4 ASTM D1621
 .sup.5 Comparative Examples
In Table 2, various operating parameters for the extrusion process are set forth, including resin rate, blowing agent rate, torque, and die pressure. The melting points (Tf) of various samples are also summarized in Table 2, as are the density, cell size and percent crystallinity. Sample numbers 2, 3, 4, 5 and 12 are in accordance with this invention. The remaining samples were provided for purposes of comparison.
                                  TABLE 2
__________________________________________________________________________
                    RESIN
                         BA       DIE             CELL
SAMPLE              RATE RATE
                             TORQUE
                                  PRESS.
                                       Tf   DENSITY
                                                  SIZE
                                                      %
NO.  COMPOSITION    (lb/hr)
                         (pph)
                             (in lb)
                                  (psi)
                                       (deg C)
                                            (pcf) (mm)
                                                      CRYSTALLINITY
__________________________________________________________________________
1    100% SPS       4.55 8.8 733.6
                                  250  257  4.31  1.62
                                                      46.98
2    80% SPS/20% MAPPO
                    4.55 8.8 1244.9
                                  1050 246  3.77  0.67
                                                      --
3    60% SPS/40% MAPPO
                    4.55 8.8 1333.8
                                  900  253  3.69  0.75
                                                      --
4    75% SPS/15% PC/10% MAPPO
                    4.55 8.8 1200.4
                                  950  245  4.34  0.62
                                                      --
5    80% SPS/15% PC/5% E601
                    4.45 8.8 1778.4
                                  850  250  5.99  0.18
                                                      --
6    94% SPS/6% PPO (.5 pph Talc)
                    5.3  8.3 1378.3
                                  --   228  3.41  0.86
                                                      49.63
7    85% SPS/15% PPO (.5 pph Talc)
                    4.6  6.5 1511.6
                                  --   215  3.89  0.54
                                                      56.89
8    74% SPS/26% PPO (.5 pph Talc)
                    4.6  6.5 1667.3
                                  --   216  4.34  1.01
                                                      59.77
9    95% SPS/5% PC  4.55 8.8 1067.0
                                  1000 --   3.5   1.01
                                                      --
10   94% SPS/6% PC (.5 pph Talc)
                    5.2  6.0 1333.8
                                  --   --   5.04  1.50
                                                      --
11   85% SPS/15% PC 4.55 8.8 1289.3
                                  750  --   3.62  1.08
                                                      --
12   75% SPS/25% PC 4.55 8.8 1022.3
                                  700  255  4.10  1.20
                                                      43.72
__________________________________________________________________________
 WP; TALC = 1.0 pph; BA = HCFC123; 1/8" ROD DIE SETUP
As can be seen by reference to Tables 1A and 1B, the foamed materials in accordance with the invention generally exhibited higher heat deflection temperatures than foamed materials obtained from substantially pure syndiotactic polystyrene, and various binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate. Additionally, by reference to the values of the comparative flex product per square inch test, it is seen that the more preferred foamed materials of this invention exhibit reduced intrinsic brittleness as compared with foamed materials obtained from substantially pure syndiotactic polystyrene, and various binary blends of syndiotactic polystyrene with either polyphenylene oxide or polycarbonate. 75% SPS and 25% PC is less preferred, since while it exhibits higher HDT, its compressive strength is less than that of 100% SPS.
By reference to Table 1B, it can be seen that the foamed materials of this invention generally exhibit improved compressive strength relative to foamed materials obtained from substantially pure syndiotactic polystyrene, and foamed materials obtained from binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate.
Table 2 illustrates that foamed materials in accordance with this invention can be successfully prepared using techniques which are generally successfully employed in preparing foamed materials from substantially pure syndiotactic polystyrene or binary blends of syndiotactic polystyrene and either polyphenylene oxide or polycarbonate.
It will be apparent to those skilled in the art that various modifications to the preferred embodiment of the invention as described herein can be made without departing from the spirit or scope of the invention as defined by the appended claims.

Claims (21)

We claim:
1. A foamed polymeric material obtained from a polymer blend comprising syndiotactic styrene polymer and an amount of an anhydride modified polyphenylene oxide which will impart a heat distortion temperature which is aleast about 130° C.
2. The polymeric material of claim 1, wherein the syndiotactic styrene polymer comprises at least 50% of the polymer blend by weight.
3. The polymeric material of claim 1, wherein the syndiotactic styrene polymer comprises from about 50% to about 80% of the polymer blend by weight.
4. The polymeric material of claim 1, wherein the polymer blend further comprises a polycarbonate.
5. The polymeric material of claim 4, wherein the polymer blend includes at least about 10% polycarbonate by weight and at least about 10% maleic anhydride modified polyphenylene oxide by weight.
6. A foamed polymeric material obtained from a polymer blend comprising at least about 50% syndiotactic styrene polymer by weight, and at least about 10% maleic anhydride modified polyphenylene oxide by weight.
7. The polymeric material of claim 6, wherein the syndiotactic styrene polymer comprises from about 50% to about 80% of the polymer blend by weight.
8. The polymeric material of claim 7, wherein the polymer blend further comprises an amorphous polymeric material other than maleic anhydride modified polyphenylene oxide.
9. The polymeric material of claim 8, wherein the amorphous polymeric material other than maleic anhydride modified polyphenylene oxide is a polycarbonate or a silicone elastomer.
10. The polymeric material of claim 6, wherein the polymer blend includes a polycarbonate.
11. A foamed polymeric material obtained from a polymer blend comprising from about 60% to about 80% syndiotactic styrene polymer by weight and from about 40% to about 20% by weight of an amorphous polymeric material, the amorphous polymeric material including at least one of maleic anhydride modified polyphenylene oxide and a polycarbonate.
12. The polymeric material of claim 11, wherein the polymer blend includes a polycarbonate.
13. The polymeric material of claim 11, wherein the polymer blend includes at least 10% maleic anhydride modified polyphenylene oxide by weight.
14. The polymeric material of claim 11, wherein the polymer blend includes a polycarbonate and maleic anhydride modified polyphenylene oxide.
15. The polymeric material of claim 11, wherein the polymer blend includes a polycarbonate and a silicone elastomer.
16. The polymeric material of claim 11, wherein the expanded polymeric material has a heat deflection temperature of at least 130° C.
17. The polymeric material of claim 11, wherein the expanded polymeric material has a heat deflection temperature of at least 200° C.
18. A foamed polymeric material obtained from a polymer blend consisting essentially of from about 60% to about 80% syndiotactic styrene polymer by weight, and from about 40% to about 20% by weight of an amorphous polymeric material comprising at least one of maleic anhydride modified polyphenylene oxide and a polycarbonate.
19. The polymeric material of claim 18, wherein the amorphous polymeric material consist essentially of polycarbonate and maleic anhydride modified polyphenylene oxide.
20. The polymeric material of claim 18, wherein the amorphous polymeric material consist essentially of polycarbonate and a silicone elastomer.
21. The polymeric material of claim 18, wherein the amorphous polymeric material consist essentially of maleic anhydride modified polyphenylene oxide.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030216503A1 (en) * 2002-05-20 2003-11-20 Merfeld Glen David Syndiotactic polystyrene blends
US6790870B1 (en) 1999-09-20 2004-09-14 North Carolina State University Methods of making foamed materials of blended thermoplastic polymers using carbon dioxide
US20130088406A1 (en) * 2010-06-04 2013-04-11 Furukawa Electric Co., Ltd. Printed circuit board, antenna, wireless communication device and manufacturing methods thereof
KR101332431B1 (en) * 2010-07-08 2013-11-22 제일모직주식회사 Flame retardant expandable polystyrene beads and method for preparing the same
JP2014504659A (en) * 2010-12-30 2014-02-24 ナノ アクティブ フィルム ソチエタ レスポンサビリタ リミテ Disordered nanoporous crystal form didiotactic polystyrene, process for its preparation and article comprising the same
US20150282258A1 (en) * 2010-10-07 2015-10-01 Jong Peter Park Microwaveable vessel

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006265526A (en) * 2005-02-25 2006-10-05 Sekisui Plastics Co Ltd Modified polyphenylene ether-based resin foam sheet and method for producing the same, and method for producing modified polyphenylene ether-based resin laminated foam sheet
WO2010012702A1 (en) * 2008-07-29 2010-02-04 Basf Se Expandable thermoplastic polymer blend
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Citations (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE369037C (en) * 1923-02-13 Otto Glase Impact device for stiffening liquids
US3449270A (en) * 1968-05-28 1969-06-10 Dow Chemical Co Method of making foamed crystalline vinyl aromatic polymer
US3449268A (en) * 1966-05-31 1969-06-10 Dow Chemical Co Process for making foamable isotactic polystyrene
US3830001A (en) * 1972-05-10 1974-08-20 Sturm Ruger & Co Revolver cylinder pin and retaining means therefor
US4185352A (en) * 1978-02-10 1980-01-29 Chemetron Corporation Scraped-surface apparatus
EP0064343A1 (en) * 1981-04-30 1982-11-10 Mobil Oil Corporation Thermally stable crystal polymers of styrenic monomers
US4420291A (en) * 1979-01-05 1983-12-13 Maryland Cup Corporation Dynamic cooler apparatus for molten thermoplastic material
US4436679A (en) * 1981-11-09 1984-03-13 Maryland Cup Corporation Method and apparatus for generating foamed thermoplastic materials
US4454087A (en) * 1981-05-18 1984-06-12 Sekisui Plastics Method and apparatus for preparing thermoplastic resin foam
US4472556A (en) * 1982-12-20 1984-09-18 Dow Corning Corporation Method for enhancing one or more mechanical properties of partially crystalline thermoplastics
DE3316838A1 (en) * 1983-05-07 1984-11-08 Hermann Berstorff Maschinenbau Gmbh, 3000 Hannover Process and tandem extruder system for producing a foamed material web of polystyrene or the like
US4491553A (en) * 1979-07-17 1985-01-01 Lion Corporation Method for producing filler-loaded thermoplastic resin composite
US4824629A (en) * 1988-02-04 1989-04-25 The Dow Chemical Company Process for preparing an oriented crystalline syndiotactic vinylaromatic polymer
US4857390A (en) * 1987-06-26 1989-08-15 General Electric Company Low density extruded foam having high compressive strength
US4859339A (en) * 1988-02-11 1989-08-22 The Dow Chemical Company Microporous membranes of syndiotactic vinylaromatic polymers
US4937272A (en) * 1988-01-13 1990-06-26 Idemitsu Kosan Co., Ltd. Expanded thermoplastic resinous materials and process for production thereof
US4946897A (en) * 1987-10-28 1990-08-07 Montedipe S.P.A. Thermoplastic compositions based on syndiotactic polymers of styrene and polyphenylene ethers
US4958933A (en) * 1988-11-25 1990-09-25 Paul Zakich Cooler-extruder device
JPH02248438A (en) * 1989-03-23 1990-10-04 Idemitsu Kosan Co Ltd Thermoplastic resin foam and its production
US4980101A (en) * 1989-07-14 1990-12-25 The Dow Chemical Company Anisotropic microporous syndiotactic polystyrene membranes and a process for preparing the same
US4985505A (en) * 1981-05-01 1991-01-15 Mobil Oil Corporation Process of dispersion polymerization of butadiene in propane or butane
CA2029164A1 (en) * 1989-12-27 1991-06-28 Richard Charles Bopp One step process for simultaneous extrusion and impregnation of blowing agent in the production of expandable thermoplastic resin particles
US5034171A (en) * 1989-11-30 1991-07-23 Air Products And Chemicals, Inc. Process for extruding thermoplastic materials using low pressure inert gases as foaming agents
US5066741A (en) * 1990-03-22 1991-11-19 The Dow Chemical Company Process for preparation of syndiotactic vinyl aromatic polymers
EP0463759A2 (en) * 1990-06-20 1992-01-02 Rapra Technology Limited Production of thermoplastics foams
JPH0427519A (en) * 1990-05-22 1992-01-30 Sanyo Kokusaku Pulp Co Ltd Manufacturing method of polystyrene resin foam sheet
US5120481A (en) * 1989-02-28 1992-06-09 U.C. Industries, Inc. Process for preparing extruded foam bodies
US5164479A (en) * 1989-01-24 1992-11-17 Idemitsu Kosan Co., Ltd. Process for preparation of molding product from syndiotactic styrene polymer
US5171834A (en) * 1988-08-31 1992-12-15 Idemitsu Kosan Co., Ltd. Solvent treatment of syndiotactic styrene-based polymer moldings
JPH05200835A (en) * 1992-01-23 1993-08-10 Jsp Corp Method for producing low expanded polystyrene resin sheet
US5250576A (en) * 1991-08-12 1993-10-05 The Procter & Gamble Company Process for preparing emulsions that are polymerizable to absorbent foam materials
US5269987A (en) * 1992-12-22 1993-12-14 Reedy Michael E Process for producing alkenyl aromatic foams using a combination of atmospheric and organic gases and foams produced thereby
TW225502B (en) * 1993-06-18 1994-06-21 Lai Advance Industry Co Ltd Method of making fine-proof polystyrene board
US5357014A (en) * 1991-08-09 1994-10-18 Idemitsu Kosan Co., Ltd. Styrenic resin molding and process for producing same
DE4325879A1 (en) * 1993-08-02 1995-02-09 Hoechst Ag Shaped structures made of a thermoplastic, process for its production and its use
US5411687A (en) * 1994-06-23 1995-05-02 The Dow Chemical Company Extruded, open-cell alkenyl aromatic polymer foam and process for making
US5460818A (en) * 1994-04-12 1995-10-24 The Dow Chemical Company Compatibilized blend of olefinic polymers and monovinylidene aromatic polymers
US5464878A (en) * 1993-06-11 1995-11-07 Camelot Technologies, Inc. Degradable polymeric form and process for making
JPH07300544A (en) * 1994-04-15 1995-11-14 Ciba Geigy Ag Stabilized halogenated polymer
US5525667A (en) * 1995-08-02 1996-06-11 Tenneco Plastics, Inc. Polymer orientation

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3830901A (en) * 1968-09-09 1974-08-20 T Winstead Continuous process for extruding cellular thermoplastics
AU628651B2 (en) * 1989-10-13 1992-09-17 Idemitsu Kosan Co. Ltd Styrene polymer composition
CA2084534A1 (en) * 1991-12-30 1993-07-01 Donald T. Liles Polystyrene modified with silicone rubber powder

Patent Citations (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE369037C (en) * 1923-02-13 Otto Glase Impact device for stiffening liquids
US3449268A (en) * 1966-05-31 1969-06-10 Dow Chemical Co Process for making foamable isotactic polystyrene
US3449270A (en) * 1968-05-28 1969-06-10 Dow Chemical Co Method of making foamed crystalline vinyl aromatic polymer
US3830001A (en) * 1972-05-10 1974-08-20 Sturm Ruger & Co Revolver cylinder pin and retaining means therefor
US4185352A (en) * 1978-02-10 1980-01-29 Chemetron Corporation Scraped-surface apparatus
US4420291A (en) * 1979-01-05 1983-12-13 Maryland Cup Corporation Dynamic cooler apparatus for molten thermoplastic material
US4491553A (en) * 1979-07-17 1985-01-01 Lion Corporation Method for producing filler-loaded thermoplastic resin composite
EP0064343A1 (en) * 1981-04-30 1982-11-10 Mobil Oil Corporation Thermally stable crystal polymers of styrenic monomers
US4985505A (en) * 1981-05-01 1991-01-15 Mobil Oil Corporation Process of dispersion polymerization of butadiene in propane or butane
US4454087A (en) * 1981-05-18 1984-06-12 Sekisui Plastics Method and apparatus for preparing thermoplastic resin foam
US4436679A (en) * 1981-11-09 1984-03-13 Maryland Cup Corporation Method and apparatus for generating foamed thermoplastic materials
US4472556A (en) * 1982-12-20 1984-09-18 Dow Corning Corporation Method for enhancing one or more mechanical properties of partially crystalline thermoplastics
DE3316838A1 (en) * 1983-05-07 1984-11-08 Hermann Berstorff Maschinenbau Gmbh, 3000 Hannover Process and tandem extruder system for producing a foamed material web of polystyrene or the like
US4857390A (en) * 1987-06-26 1989-08-15 General Electric Company Low density extruded foam having high compressive strength
US4946897A (en) * 1987-10-28 1990-08-07 Montedipe S.P.A. Thermoplastic compositions based on syndiotactic polymers of styrene and polyphenylene ethers
US4937272A (en) * 1988-01-13 1990-06-26 Idemitsu Kosan Co., Ltd. Expanded thermoplastic resinous materials and process for production thereof
US4824629A (en) * 1988-02-04 1989-04-25 The Dow Chemical Company Process for preparing an oriented crystalline syndiotactic vinylaromatic polymer
US4859339A (en) * 1988-02-11 1989-08-22 The Dow Chemical Company Microporous membranes of syndiotactic vinylaromatic polymers
US5171834A (en) * 1988-08-31 1992-12-15 Idemitsu Kosan Co., Ltd. Solvent treatment of syndiotactic styrene-based polymer moldings
US4958933A (en) * 1988-11-25 1990-09-25 Paul Zakich Cooler-extruder device
US5164479A (en) * 1989-01-24 1992-11-17 Idemitsu Kosan Co., Ltd. Process for preparation of molding product from syndiotactic styrene polymer
US5120481A (en) * 1989-02-28 1992-06-09 U.C. Industries, Inc. Process for preparing extruded foam bodies
JPH02248438A (en) * 1989-03-23 1990-10-04 Idemitsu Kosan Co Ltd Thermoplastic resin foam and its production
US4980101A (en) * 1989-07-14 1990-12-25 The Dow Chemical Company Anisotropic microporous syndiotactic polystyrene membranes and a process for preparing the same
US5034171A (en) * 1989-11-30 1991-07-23 Air Products And Chemicals, Inc. Process for extruding thermoplastic materials using low pressure inert gases as foaming agents
CA2029164A1 (en) * 1989-12-27 1991-06-28 Richard Charles Bopp One step process for simultaneous extrusion and impregnation of blowing agent in the production of expandable thermoplastic resin particles
US5066741A (en) * 1990-03-22 1991-11-19 The Dow Chemical Company Process for preparation of syndiotactic vinyl aromatic polymers
JPH0427519A (en) * 1990-05-22 1992-01-30 Sanyo Kokusaku Pulp Co Ltd Manufacturing method of polystyrene resin foam sheet
EP0463759A2 (en) * 1990-06-20 1992-01-02 Rapra Technology Limited Production of thermoplastics foams
US5357014A (en) * 1991-08-09 1994-10-18 Idemitsu Kosan Co., Ltd. Styrenic resin molding and process for producing same
US5250576A (en) * 1991-08-12 1993-10-05 The Procter & Gamble Company Process for preparing emulsions that are polymerizable to absorbent foam materials
JPH05200835A (en) * 1992-01-23 1993-08-10 Jsp Corp Method for producing low expanded polystyrene resin sheet
US5269987A (en) * 1992-12-22 1993-12-14 Reedy Michael E Process for producing alkenyl aromatic foams using a combination of atmospheric and organic gases and foams produced thereby
US5464878A (en) * 1993-06-11 1995-11-07 Camelot Technologies, Inc. Degradable polymeric form and process for making
TW225502B (en) * 1993-06-18 1994-06-21 Lai Advance Industry Co Ltd Method of making fine-proof polystyrene board
DE4325879A1 (en) * 1993-08-02 1995-02-09 Hoechst Ag Shaped structures made of a thermoplastic, process for its production and its use
US5460818A (en) * 1994-04-12 1995-10-24 The Dow Chemical Company Compatibilized blend of olefinic polymers and monovinylidene aromatic polymers
JPH07300544A (en) * 1994-04-15 1995-11-14 Ciba Geigy Ag Stabilized halogenated polymer
US5411687A (en) * 1994-06-23 1995-05-02 The Dow Chemical Company Extruded, open-cell alkenyl aromatic polymer foam and process for making
US5525667A (en) * 1995-08-02 1996-06-11 Tenneco Plastics, Inc. Polymer orientation

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6790870B1 (en) 1999-09-20 2004-09-14 North Carolina State University Methods of making foamed materials of blended thermoplastic polymers using carbon dioxide
US20030216503A1 (en) * 2002-05-20 2003-11-20 Merfeld Glen David Syndiotactic polystyrene blends
US6894102B2 (en) 2002-05-20 2005-05-17 General Electric Syndiotactic polystyrene blends
US20130088406A1 (en) * 2010-06-04 2013-04-11 Furukawa Electric Co., Ltd. Printed circuit board, antenna, wireless communication device and manufacturing methods thereof
KR101332431B1 (en) * 2010-07-08 2013-11-22 제일모직주식회사 Flame retardant expandable polystyrene beads and method for preparing the same
US20150282258A1 (en) * 2010-10-07 2015-10-01 Jong Peter Park Microwaveable vessel
US10098190B2 (en) * 2010-10-07 2018-10-09 Jong Peter Park Microwaveable vessel
JP2014504659A (en) * 2010-12-30 2014-02-24 ナノ アクティブ フィルム ソチエタ レスポンサビリタ リミテ Disordered nanoporous crystal form didiotactic polystyrene, process for its preparation and article comprising the same

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